Well that's not really a computer name its the user account name you are logging onto the machine with. Even if you don't see a logon screen its still using an account you setup to auto-login.
I think the solution is quit using your user documents area....that's just where Windows wants you to work but break free and use your hard drive however you like. I always create a directory called "c:\xLights". Then under there I have all the years. Then under each year I have Christmas, Halloween, P10 Panel, and other show folders. I also have a "c:\xLights\users" directory where I store all the show folders for users I help. My favorite show folder for testing is "c:\xLights\users\TotalNoob". Then when some users need help that annoy me I use "c:\xLights\users\total_loser". I wonder how many of them were smart enough to notice the show folder when I show them a video of things working...lol.